Roof supporting means for mines



Nov. 9, 1965 J. w. sEDDoN 3,216,202

ROOF SUPPORTING MEANS FOR MINES Filed Nov. 9, 1962 2 Sheets-Sheet 1 A Ar'ronNaYs Nov. 9, 1965 J. w. sEDDoN ROOF SUPPORTING MEANS FOR MINES 2 Sheets-Sheet 2 Filed NOV. 9. 1962 INVENTOR: JEFFREY W. SEDDON BY Ww m,

ATTO R NEYS United States Patent O 3,216,202 ROOF SUPPORTING MEANS FDR MINES Jeffrey W. Seddon, Standish, England, assignor to Gullick Limited, Wigan, England, a British company Filed Nov. 9, 1962, Ser. No. 236,498 8 Claims. (Cl. 61-45) This invention is for improvements in or relating to roof supporting means for mines.

The invention is more particularly, although not exclusively concerned with self-advancing or Walking roof supports. Such supports incorporate means (e.g. a hydraulic ram device or devices) which enable the support to move itself forwardly as strip-ping or cutting of the coal face proceeds, the support also serving generally to push over the coal conveyor to the newly exposed coal face.

One object of the present invention is to provide a roof support with a mechanically extendable roof bar Which can be advanced as necessary to offer resistance to newly exposed roof in the region of the cutter track and is also capable of adjusting itself to conform to roof irregularities in the region to which it is advanced.

According to the present invention there is provided a roof support having a main roof supporting beam which projects cantilever fashion from the support, wherein said main beam is provided with an extension bar adapted to be advanced with respect to the main beam, rsaid extension bar being carried so that it can adjust itself to conform to roof irregularities.

Preferably the extension bar is adapted to be advanced manually.

In a preferred embodiment of the invention the extension bar is mounted for angular movement so that it can adjust itself or be adjusted to conform to roof irregularities.

Conveniently the extension bar is somewhat telescopically mounted in the main beam and is adapted to pivot on supporting members thereof.

The extension bar may be secured after it has been advanced to the required amount by means of a wedge driven into it laterally and adapted to bear against the main beam.

One particular embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings wherein:

FIGURE 1 is an elevation partly in section of the roof support,

FIGURE 2 is a section on the line H II of FIGURE 1,

FIGURE 3 is a further cross-sectional view, and FIGURE 4 is a fragmentary view showing a modification.

Referring to the drawings, the support comprises two propping units or elements. One of these units (hereinafter referred to as the rear unit), comprises a base having sockets in which are mounted four hydraulically extensible props or legs 11 which support at their upper parts a roof bar structure 12.

The other unit (hereinafter referred to as the forward unit) comprises a foot 13 having a socket in which is mounted a single hydraulically extensible leg or prop 14.

A cantilever form of roof beam 15, 16 is articulated to the roof bar structure 12 as indicated at 17 and rests on the upper part of the single leg 14 of the forward support unit. It Will be noted that the cantilever roof beam 15, 16 is provided on its underside With a concave seating 18 which bears on a convex upper part of the leg or prop 14 so that the one can accommodate itself to the other.

Located on a platform 19, secured between the unit 10 and the foot 13, is a double-acting hydraulic ram R, the thrust-bar or piston rod of which passes freely through 3,216,202 Patented Nov. 9, 1965 ICC an arch in the foot 13 and is adapted to be coupled as indicated at 20 to a bracket 21 on the coal conveyor C.

After a cut of the coal face has been made the ram can be operated to push over the coal conveyor to the newly exposed coal face and then, by lowering the props 11 and 14 and retracting the ram, the roof support comprising the two units is drawn up to the conveyor. The chock is then re-secured between floor and roof.

Chocks or roof supports as just set forth, and their mode of operation, are more fully described in the specication of application for patent No. 89,l59.

For the purpose of the present invention the forward part 16 of the main cantilever beam 15, 16 is of somewhat box-section comprising a top plate 16a, side walls 16b and bottom flanges 16C which are spaced apart so as to provide a gap 22 between them.

Slidably supported within the box-like structure of the part 16 of the main beam is an extendable bar adapted to be advanced from the position shown in full lines in FIGURE l to the position shown in chain lines. This extendable bar comprises a longitudinal member 23, slidably located in the gap 22, and having an enlargement 24 at its rear end provided With a through opening 25. The longitudinal member 23 has secured to it a top plate 26 adapted to bear against the roof.

The extendable bar also includes a laterally extending pivot bar 27 of semi-circular cross-section adapted to pivot on the inwardly directed parts or llanges of the plate 16C.

When the coal cutter or the like has made a cut at the coal face the extendable bar can be advanced immediately so as to oifer resistance to the newly exposed roof in the region of the cutter track. When it has been advanced to the required position it is secured against the roof by means of a wedge 28 which is driven through the opening 25 in the rear part of the extendable bar and is adapted to bear against the underside of the plate 16C as shown in FIGURE 3 and against stops 29' provided towards the forward end of the main beam part 16.

It will be appreciated that when the main support is advanced forwardly as previously described the extendable bar will automatically be retracted or pushed back into the part 16 of the main beam.

The pivot part 27 enables the extendable bar to move angularly so as to conform with roo-f irregularities in the region to which it has been advanced.

The support for, and ysystem of covering, the cutter track as above -described has the advantage over previous arrangements, using self-advancing supports, that it is not necessary to release any of the 'supporting props of the roof during operation and therefore the main roof support system is undisturbed.

Furthermore, the operation of advancing the extendable bar can be done from a safe position, i.e. from the normal travelling track which is situated between the conveyor and the main roof support. The part 16 of the main beam which houses the extendable bar forms a cover during this operation.

The wedge mechanism is part of the extendable bar and therefore there is no obstruction to the passage of the cutting machine when the extendable bar is in its retracted position.

The 'design of the extendable bar is such that it can easily be litted underground to existing supports which warrant the inclusion of such an extension.

In the modification shown in FIGURE 4 the Wedge 28 is replaced by a rotary cam 30 having a stem 31 rotatably supported in ya bore 32 in the part 24 of the extendable bar 23. The head of the cam bears against the top plate 16a of the cantilever bar 16. The cam 30 and the bar 23 have co-operating inclined faces 33 and 34 respectively so that rotation of the stem or shaft 31, by means of a tommy bar inserted in a hole 35, causes it to move axially 3 v and raise or lower the extension bar angularly about the pivot 27.

I claim:

1. In a mine roof support, the combination of a roof supporting beam having a tubular longitudinal housing portion including a longitudinally extending opening through one wall thereof, an extension bar slideably mounted in said housing portion for advancing and retracting movements longitudinally of said beam, pivot means between said b-ar and beam to permit relative vertical angular movements therebetween, guide means protruding from said extension bar into said longitudinal yopening for guiding the longitudinal movements of the bar, and tilt means carried by said extension bar for rocking the bar -about rsaid pivot means to adjust the bar to conform to roof irregularities, said tilt means including a wedge device interposed between the extension bar and the roof supporting beam and carried by a portion of said tilt means projecting through said longitudinal opening for applying a tilting force to said wedge device.

2. The combination according t-o claim 1 wherein said wedge device comprises a rotatable annular inclined plane mechanism.

3. The combination according to claim 1 wherein said pivot means is fixed to said extension bar and movable therewith, said pivot me-ans comprising a semi-circular rib extending transversely of said extension bar.

4. The combination according to claim 1 wherein said roof supporting beam is a cantilever having a substantially horizontal support pivot axle at one end and is a-dapted to be supported substantially near its center, -said housing portion extending to the other end, whereby the extension bar is movable to extended positions protruding from said other end of the cantilever.

5. The combination according to claim 1 wherein said housing portion of the roof supporting beam comprises a top plate, side walls and inwardly directed bottom flanges which are spaced apart to form said longitudinally extending -opening between them, said extension bar being substantially completely housed within said housing portion when completely retracted.

6. The combination according to claim 5 wherein at least a portion of said extension bar is T-shaped in cross section, the leg of said T forming said guide means and being seated for guided movement in said longitudinal opening.

7. The combination according to claim 6 wherein said leg of the T portion of the extension bar projects downwardly below said bottom flanges of the beam to form said portion of the tilt means which carries the wedge device and is provided with an aperture therethrough, said wedge device comprising a wedge shaped plate extending vertically through said aperture and laterally of said extension bar.

8. A self-advancing mine roof support comprising a pair of roof support units each having a base linked to each other and disposed one behind the other for location adjacent a conveyor, a uid pressure advancing ram operatively connected to the base of one of said units and adapted to be connected to lsaid conveyor to independently advance the conveyor and the units as -a pair, a plurality of pressure fluid extensible props mounted front to rear on the base of said rear unit, a roof-supporting beam mounted on said props for application thereby to a roof, a cantilever beam pivoted for vertical movements to the forward end of said roof-supporting beam and projecting forwardly a substantial distance beyond the base of said forward unit, at lea-st one pressure-fluid extensible prop mounted on the base of said forward unit pivotally supporting a central part of said cantilever beam, said cantilever beam having a tubular housing portion of substantial length and including a longitudinally extending opening through one w-all thereof, an extension bar slideably mounted in said housing portion for advancing and retracting movements longitudinally of said cantilever beam, pivot means between said extension bar and cantilever beam to permit vertical angular movements of the bar with respect to the beam, guide means protruding from said extension bar into said longitudinal opening for guiding the longitudinal movements of the bar, and tilt means carried by said extension bar for rocking the bar about said pivot means, said tilt means including a wedge device interposed between the extension bar and the cantilever beam and carried in an aperture in a portion of said tilt means which projects through said longitudinal opening.

References Cited by the Examiner UNITED STATES PATENTS 2,694,293 l l/ 54 Perrin et al 6145.2

FOREIGN PATENTS 1,163,475 4/ 5 8 France.

928,887 6/55 Germany. 1,087,098 1/56 Germany.

847,934 9/ 60 Great Britain. 882,933 1 1/ 61 Great Britain.

OTHER REFERENCES German printed application B 27,983, November 1956, KI, 5c 10.01.

CHARLES E. OCONNELL, Primary Exqminer. EARL L WITMER, Examiner- 

1. IN A MINE ROOF SUPPORT, THE COMBINATION OF A ROOF SUPPORTING BEAM HAVING A TUBULAR LONGITUDINAL HOUSING PORTION INCLUDING A LONGITUDINALLY EXTENDING OPENING THROUGH ONE WALL THEREOF, AN EXTENSION BAR SLIDEABLU MOUNTED IN SAID HOUSING PORTION FOR ADVANCING AND RETRACTING MOVEMENTS LONGITUDINALLY OF SAID BEAM, PIVOT MEANS BETWEEN SAID BAR AND BEAM TO PERMIT RELATIVE VERTICAL ANGULAR MOVEMENTS THEREBETWEEN, GUIDE MEANS PROTRUDING FROM SAID EXTENSION BAR INTO SAID LONGITUDINAL OPENING FOR GUIDING THE LONGITUDINAL MOVEMENTS OF THE BAR, AND TILT MEANS CARRIED BY SAID EXTENSION BAR FOR ROCKING THE BAR ABOUT SAID PIVOT MEANS TO ADJUST THE BAR TO CONFORM TO ROOF IRREGULARITIES, SAID TILT MEANS INCLUDING A WEDGE DEVICE INTERPOSED BETWEEN THE EXTENSION BAR AND THE ROOF SUPPORTING BEAM AND CARRIED BY A PORTION OF SAID TILT MEANS PROJECTING THROUGH SAID LONGITUDINAL OPENING FOR APPLYING A TILTING FORCE TO SAID WEDGE DEVICE. 